Comma separated CSS selectors are exploded with commas

[rndmerle]

Hi!

From version 2.3.0, any combined CSS selectors (with coma) are quite destroyed :p Input CSS:

.entity-enter-to,
.entity-leave {
  opacity: 1;
}

Ponyfill's output CSS copied from IE11 DOM:

.,e,n,t,i,t,y,-,e,n,t,e,r,-,t,o,,,
,.,e,n,t,i,t,y,-,l,e,a,v,e{opacity:1;}

If you have no idea where it comes from I can try to find more infos. (single selectors are fine)

[jhildenbiddle]

@rndmerle --

I put together a quick StackBlitz demo using 2.3.1 of the ponyfill and I'm not seeing this issue.

Can you create a demo for review?

[rndmerle]

Ok I spent hours digging code and testing setups. It happens only when all these conditions are met:

• core-js es.regex.exec shim is included in the build
• using css-vars-ponyfill 2.3.0+
• running the code with IE11
• the CSS contains a var() within a calc()

Then output for:

:root {
  --layout-gutter: 1rem;
}

.whatever,
body {
  background: lightsteelblue;
}

.app {
  margin: calc(var(--layout-gutter));
}

is:

<style data-cssvars="out" data-cssvars-job="2" data-cssvars-group="1">.,w,h,a,t,e,v,e,r,,,
,b,o,d,y{background:lightsteelblue;}.app{margin:calc(1rem);}</style>

I tried to reproduce it on js-bin (because it supports IE11) using core-js-bundle but it's not breaking, I'm not sure the regexp.exec shim is applied.

I'll maybe look into that later again.

[jhildenbiddle]

FWIW, I discovered glitch.com projects also work in IE11. Just launch your project's preview in a new window, then copy/paste the preview window's URL into IE11.

[rndmerle]

Apparently the IE11 support on Glitch is not yet available. Anyway, I spent some more hours trying to set-up a minimal reproduction repo but it's even more complicated and inextricable than I thought.

I actually gave up :( The farthest I could go was to find it was related to es.string.split not being polyfilled while es.regexp.exec was. But it's more complicated it seems.

Considering the fact that I've an easy workaround, that it seems nobody else has this issue, and that even if I could coin the real cause it would still take hours to fix, I think it's not reasonable to spend more time on this.

[jhildenbiddle]

Sounds good. Appreciate the effort, @rndmerle.

If for some reason you decide to dive back in and there is something I can do to help, give me a shout. I'll close this issue for now, but I'm happy to reopen if/when necessary.